The federal Liberals are urging Conservative Leader Andrew Scheer to attend the Ottawa Pride parade after circulating a video of him speaking out against same-sex marriage during a debate in the House of Commons 15 years ago.

Public Safety Minister Ralph Goodale tweeted a video of Scheer’s April 2005 speech opposing the Civil Marriage Act, which legalized same-sex marriage in Canada later that year.

In the speech, Scheer says that while same-sex partners can live together and love each other in lifelong, monogamous relationships, they could not really be considered married because they cannot have children in a “natural” way.

The majority of Conservative MPs voted against the bill, as did a number of Liberal MPs.

To be a leader for all Canadians, the Conservative Party leader should now end his lifelong boycott of Pride events and explain whether he would still deny same-sex couples the right to marry, as he said in Parliament. pic.twitter.com/5WEyja6Ov5

Scheer has softened his stance on same-sex marriage since then, supporting a move to erase the traditional definition of marriage from the Conservative Party of Canada’s policy book at its 2016 convention.

But the Conservative leader, whose office did not immediately respond to a request for comment, has declined to march in Pride parades.